Electrical boxes are commonly used to provide electrical service at convenient locations within buildings. The electrical boxes are commonly formed of plastic or metal and are usually securely fastened by screws or nails to the framework to the building. In newly constructed buildings, the open face of the electrical box, in which an electrical device such as an outlet or switch will be mounted, is usually flush with the surface of the wall or ceiling in which it is installed.
To solve this problem, box extenders of several different types have been developed including both metal and plastic box extenders.